<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    function parent() {
        parent.prototype.po = function (){
            console.log(123)
        }
        this.kl= function (){
            console.log('start');
        }
    }

    function Son(){
        Son.prototype.om = function (){
            console.log(234)
        }
        // Son.prototype = new parent();

    }

    Son.prototype = new parent();

   var son = new Son();
   var parent = new parent();
   // console.log(parent.__proto__.kl())
    // console.log(Son.prototype);
    console.log(son.__proto__.__proto__.po());
   // if( Son.__proto__ === Function.prototype ){
   //     console.log(2)
   // }
   //  if(Son.prototype === son.__proto__){
   //      console.log(1)
   //  }
   // var parent = new parent();
   // son.__proto__ = new parent();
   // console.log(son.po())

    function Test(){
        Test.prototype.get = ()=>{
            this.age = 5;

        }

        this.get();

    }

   var test =  new  Test();
    console.log(test.age)
</script>
</body>
</html>